James l



March 8, 1932.

J. L. M FARLAND HEAT TREATING APPARATUS Filed June 6, 1928 2Sheets-Sheet 1 'lllll ill a Invenf'or' I James L.Mc Far-land,

u/lav His Affor'ne'g.

March 8, 1932.

Fig. 3.

J. L. M FARLAN D HEAT TREATING APPARATUS Filed June 6. 1928 2Sheets-Sheet 2 His Aflor'neg.

Patented Ma 8,1932

UNITED STATES PATENT [oFFIcE JAMES L. KCFABLAN D, OF SCHENECTADY, NEWYORK, ASBIGNOR TO GENERAL ELMO I COMPANY, A CORPORATION OF NEW YORK HEATTREATING APPARATUS Application filed June 6, 1928. Serial no. 285,329.

This invention relates to heat treating) apparatus, and the like, andhas for its ject the provision of improved means for carrying out aredetermined succession of treating operations.

' Although my invention may be used in the charging of furnaces, ovensand the like, in general, it has particular application to vitreousenameling installations wherein a plurality of furnaces or ovens areused to carry out the process of enameling. In certain vitreousenameling processes, the articles to be enameled, after being dipped orsprayed with the enameling solution are placed in a preheating or dryingfurnace or oven, of relatively low temperature in which the liquidbinder used in the enamel is evaporated. The articles are then withdrawnfrom this drying furnace and conveyed into a second furnace which may betermed a firing furnace and which is maintained at a higher temperature,wherein the heating operation is completed, the constituents of theenamel being fused onto the article bein coated. After the completion ofthe heating operation in the second furnace, the articles are removedand allowed to cool after which the may be given a second application ofliqui enamel, which is then successively dried and fired in thefurnaces. The articles are often given several applications of enamel inorder to obtain a coating of the desired thickness and quality. Thedrying and firing operations are of but short duration, in someinstances a period of but a few minutes being required for eachoperation. It is advantageous therefore to operate the furnacescontinuously and remove the charge while hot at the end of eachoperation, a fresh charge being immediately inserted.

My invention has special reference to means for facilitating theinsertion and removal of the charge from the furnace or furnaces incarrying out the enameling or other process and the transfer of thecharge as desired, such as from one furnace to another where a pluralityof furnaces are used, or from a furnace to a suitable cooling rack. Incarrying out my invention in one form I provide a carriage, and a frameon the carria e which may be raised and lowered, toget er with a forkmounted on the frame so as to be movable into a furnace chamber to de-'posit or receive a charge. In connection with an enameling installationin which both drying and firing furnaces are used I provide apparatusforwithdrawing a charge from the drying furnace and concurrently there-'with withdrawing a charge from the firing furnace,and then, concurrentlydepositing the first charge in the firing furnace and the second chargeon a suitable support. My entire apparatus can easily be controlled andoperated by one person.

For a more complete understanding of my invention reference may be hadto the accompanying drawings wherein Fig. 1 is a plan view of a completeinstallation; Fig. 2 is a sectional elevation on the lines 2-2 of Fig. 1looking in the direction of the arrows; Fig. 3 is a view similar to Fig.2 but with the charging forks in the elevated position; Fig. 4 is anelevation partly in section through one of the furnaces while Fig. 5illustrates a slight modification.

Referring to Fig. 1 of the drawings, I have illustrated my invention inone form as applied in an installation for vitreous enameling comprisinga drying furnace and a firing furnace 11. In carrying out my invention Iprovide a charging device comprising a carriage 12 by means of which theheated articles 14 are carried from the furnace 10 to the furnace 11,and from the furnace 11 to the conveyor 13. While I have shown thearticles 14 as substantially cubic boxes it is to be understood that myapparatus is capable of being used with articles of any other shape,such asflat plates, for example. The furnaces 10 and 11 may bemaintained at equal temperatures but it is preferred that while beingused in the process of vitreous enameling, the furnace 10 will serve asa preheating or evaporating furnace, and thus will be maintained at alower temperature than furnace 11. A chain conveyor 15 is provided onwhich the articles 14 are placed, after having been dipped orsprayedwith the vitreous solution, and carried into the furnace 10. I haveshown the conveyor 15 as comprising an endless chain 16 passing aroundsprockets 17, one only of which is shown in Fig. 2. The links of thechain 16 are provided with rojections 18 which serve to support thearticles 14 while they are being heated in the furnace 10. After thearticles 14 have been dried in furnace 10 they are conveyed to thefiring furnace 11 where the constituents of the enamel coating arefused. After being fired, the articles are removed from furnace 11 anddeposited on the conveyor 13. The conveyor or support 13, as shown inFig. 1, may be similar to the conveyor 15 and is provided to carry thearticles 14 to a position where they may receive another coat of enamel.It is to be understood that the articles 14 need not be placed directlyon the conveyors 15 but may be placed on separate supporting members,not shown, which in turn would be supported directly on the conveyors.The use of separate supporting members would be especially applicablewhere the articles 14 to be heated are small, as the danger that thearticles might slip off of or through the conveyors would thus beavoided.

As illustrated more clearly in Fig. 4, the furnace ll comprisesrefractory walls 19 surrounded by sheet metal shells 20. Verticallymovable doors 21 are adapted to close openings 22 through which thearticles 14 are inserted into and removed from the furnaces. Heatingresistors 23 are provided in the top and bottom of the furnace 11 andrefractory, pointed supports 24 for the articles 14 are mounted abovethe lower heating resistor 23. The furnace 10 is similar to the furnace11 as indicated in Fig. 2 with the exception that the conveyor chain 16serves to support the articles 14. Heating means. not shown, is alsoprovided for furnace 10 but it is not necessary that the heating meansfor furnace 10 have as great heat generating capacity as the heatingmeans used in furnace 11. since the function of the furnace 10 is merelyto preheat the articles 14 and to cause evaporation of the liquid binderin the solution which has been sprayed on the articles 14, previous totheir entrance into the furnace 10. The back or right-hand end of thefurnace 10 may be open at all times as is illustrated in Fig. 1.

Extending substantially at right angles to the longitudinal axes of thefurnaces 10 and 11 are tracks 25, and movablv mounted on these tracks isthe charging device comprising a carriage 12 of substantiallyrectangular shape, formed of two pair of longitudinal channel beams 26and 27 connected by pairs of cross bars 28, 29 and 30. The longitudinalbeams 26 and 27 are held in proper spaced relation by the cross bars 28,29 and 30. The carriage 12 is supported on the tracks 25 by means offour wheels 33. A. reversible motor 34 mounted on the cross bars 29 isconnected to two of the wheels 33 by means of worm and pinion 35, shaft36 and gearing 37. By

energizing motor 34 the carria e 13 may thus be moved on the tracks 25.ounted on the cross bars 28-is a platform 38 and on this platform 38 aremounted control instruments and a reversible motor 40, the purpose ofwhich will be ex lained hereinafter.

Supported by t e beams 26 and 27 are two track frames 31 and 32, eachtrack frame comprising a pair of track bars 41 and a plurality of shortchannel beams 42, and as shown more clearly in Fig. 2, these channelbeams 42 are adapted to rest u on the longitudinal channel beams 26, 27.ngle irons 42-a are secured to the lon itudinal beams 26, 27 and serveto prevent ongitudinal movement of track bars 41 While still allowingvertical movement thereof. The track frames 31, 32 serve to supportcharging forks 43 and 44. The charging forks 43, 44 are each shown ascomprising three rods or tines 44a and on the upper surface of each tineis a plurality of short projections 45. The tines are secured togetherat one end and at a point substantially at the middle by cross bars 46,and it will be observed that this arrangement leaves the tinesprojecting for about half their length so that they can pass freely intoand out of the furnaces between the chains 16 in the case of furnace 10and between longitudinal rows of the refractory supports 24 in the caseof furnace 11. Secured to the left-hand end of the forks 43, 44, asviewing Figs. 1, 2 and 3, are shafts 47 and attached to the ends ofthese shafts and mounted within the channels of track bars 41 arerollers 48. The rollers 48 are slightly smaller in diameter than thewidth of the channel in track bars 41 and the left-hand ends of theforks 43 and 44 are thus mounted for movement lengthwise of the trackbars 41. At the opposite or righthand end of track bars 41 are mountedshort shafts provided with rollers 49 on which the right-hand ends oftines 44a rest so as to be supported thereby. I have provided means formoving the forks 43, 44 lengthwise of the track frames 31, 32 and thismeans comprises shafts 50 and 50a driven by motor 40 and secured todrums 51 and 51a mounted at the left-hand ends of the track frames.Idler pulleys 52 are supported by the track frames 31, 32 and passingaround these idler pulleys, drums 51 51a and secured to the left-handends of forks 43, 44 are flexible members 53, preferably made of heatresistant wire or cable. The motor 40 is connected to shafts 50, 50a bymeans of a worm and pinion 54 and the clutches 55 and 56. It will beseen that by operating the motor 40 the drums 51 and 51a will be rotatedand by means of the flexible members 53 will cause forks 43, 44 to movelengthwise relatively to the track frames 31, 32. The clutches 55, 56are preferably of the magnetic type, having control means, not shown, onthe control platform 38. By means I have also provided means for raisingandv lowering the track frames 31, 32 and consequently therewith .theforks 43, 44 vertically relatively to the carriage 12, and this meanscomprises reciprocating piston motors 57 .and 58 which maybe of ahydraulic or pneumatic type, linkage 59 and a pair of bell cranks 60.Attached to the upper arms of bell cranks 60 are anti-friction rollers61 which serve to en age the lower surfaces of.

track bars 41'an act as supports therefor. It will be observed that bycausing the pistonsof the motors 57, 58 to move to the right, the armsof the bell cranks to which the rollers 61 are secured, will be raisedfrom the position shown in Fig. 2 and the linkage 59,-

track frames 31, 32 and forks 43,44 will then be in the position shownin Fig.- .3. As will be observed with reference to Figs. 2, 3 and 4,when the track frames 31, 32 and forks 43,

' 44 are in the lower position (Figs. 2 and '4) the upper surfaces ofthe forks 43, 44 will be slightly lower than the uppersurface of theconveyor 15 of furnace 10 and the upper extremities of the pointedrefractory supports 24 of furnace 11.

An important feature of my invention is the simplicity with which myentire apparatus may be operated and controlled by one person. Anoperator standing on the platform 38, by manipulatingthe controllers 62and 63 causes the motors 34 and 40 to be energized and thus governs boththe lateral movement of the carriage 12 and the longitudinal movement ofthe forks 43 and 44. By moving the levers 64, either one or both of thepneumatic motors 57, 58 may be operated to raise and lower the trackframes 31, 32. Three pair of push buttons 65 serve to controlrespectively the upward and downward movement of the furnace doors 21and the movement of the conveyor 15.

In explaining the operation of my apparatus let us assume that a numberof the articles 14, having been coated with enameling solution, areresting on the conveyor 15 in the furnace 10 and that a number of thearticles are also resting on the refractory supports 24 in furnace 11,-as shown in the drawings. With the carriage 12 in the position shown inFig. 1 and with the track frames 31 32 and forks 43, 44 in the lowerposition, as shown in Fig. 2, the operator causes doors 21 to be raisedand causes motor 40 to be energized in the proper direction to move thetinesof the forks 43, 44 into the furnaces 10 and 11 immediatelyunderneath the articles 14. It will be understood that the tines of theforks move between the supports for the articles in the furnaces. Forexample, in furnace 10 the tines will move between the chains of theconveyor 15; while is the furnace 11. the males will be supported onrelatively narrow spaced supports extending lengthwise of the furnace,and between which the tines of the fork are free to move under thearticles. The mo-f tors 57,58 are now operated and raise thetrack'frames 31, 32 and forks '43, 44 to the upper position and thetines of'the forks 43,

44 will thereby lift the articles 14'verticall from the supports inthefurnaces 10 andfl While the forks are maintained in this raisedposition the motor 40 is operated in a reverse direction and the forks43 44 and articles 14 will thus be withdrawn. from the furnaces. Thedoors 21 are then closed by the-operator on platform 38. 'The motor 34is then ener-- gized and becauseof the driving connection between thismotor and one pair of the wheels 33 the entire carriage 12- will bemoved toward the conveyor 13. When. the vtrack frames 31 and 32 are inalignment, respectively, with the conveyor 13 and furnace 11, themovement of the carriage'is stopped, the door 21 of furnace 11 israised, and the motor 40 being energized in the proper direction causesthe forks 43,44 to move the articles 14 carried thereby to positionsdirectly over conveyor 13 and directly over the refracto supports 24. Byoperating motors 57, 58 in the reverse direction the track frames'31, 32and forks 43, 44 are verticallv lowered and the articles 14, carried bythe forks will be deposited on theconveyor 13 and on the refractorysupports 24 in furnace 11. The articles on the conveyor13 may then bemoved to a position where they may receive a second coat of enamel. Themotor 40 is now energized in a direction to move the forks 43, 44 to theleftand then the motor 34 is energized in a reverse direction wherebythe carriage 12 is moved back to its former position, as shown in Fig.1, and the entire operation may then be repeated. It is to be understoodthat when a charge of articles 14 is withdrawn from furnace 10 byfork.44, additional articles will be moved into the furnace 10 on theconveyor 15.

Should the operator wish to move but'one of the forks 43 or 44 he hasbut to disconnect the opposite clutch 55 or 56, suitable means, notshown, being provided for the purpose, and the operation of theapparatus will then be the same as described heretofore, with the excetion that but one of the forks 43 or.44 will be in use.

In the enameling of flat plates and other articles which have but littlestiffness it sometimes happens that the'se articles will be warped whileresting on the tines 44a of forks 43,44 due to sagging of those portionsof the articles overlapping the tines, and for the purpose of preventingthis I have rovided, as shown in Fig. 5, a slight modi cation in whichan additional pair of forks 66 are mounted in fixed relation to thelongisubstantially the same as that described heretofore, the onlyexception bein that on the withdrawal of the forks 43, 44 romthefurnaces 10 and 11 the operator causes the forks to be lowered to theposition shown in Fig. 2. The flat plates or articles will then besupported not only on the tines 44a but also on the stationary forks 66.Should the articles remain on the forks outside of the furnace.

for an appreciable time warpage of the plates or artic es will berevented since the edges of the articles over apping the tines 44a willbe supported on the stationary forks 66.

While I have described my invention as embodied in concrete form andoperating in a specific manner in accordance with the rovisions of thepatent statutes, it should be understood that I do not limit myinvention thereto, since various modifications thereof will suggestthemselves to those skilled in the art without departing from the spiritof my invention, the scope of which is set forth in the annexed claims,

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. Charging means for a plurality of furnaces, comprlsin a carriage, aplurality of charge carrying evices mounted on said carriage, saiddevices each being arranged to lift and carry a charge for said urnaces,driving means for moving said carriage to bring said charge carryingdevices concurrently into registering relation with said furnaces,driving means for moving said charge carrying devices into and out ofsaid furnaces, driving means for raising, lowering said charge carryingdevices and means for controlling said driving means and auxiliary meansfor chargin one of said furnaces independently of said c arging devices.

2. The combination with a plurality of furnaces arranged in parallelrelation, charge carrying means therefor comprising a plurality ofvertically movable frames arranged substantially in parallel with eachother and with said furnaces, said frames having substantially the samespacing as said furnaces, charge carrying and lifting devices supportedby said frame, driving means for moving said charging devices into andout of said furnaces, driving means for raising and lowering said framesto raise and lower the chargeand means for selectively driving means.

3. The combination with a pair of furnaces arranged substantially inparallel relation, of charging apparatus for said furnaces comprising atrack mounted substantially at controlling said angles to said furnacesand right angles to said furnaces, a pair of elongated verticall movableframes supported by said track an separated a distance equal to thedistance between said furnaces, charging forks supported by said framesand mounte for horizontal movement relative to said frames, drivingmeans for raising and lowering said frames, driving means for movingsaid forks on said frames into and out of said furnaces, means forcontrolling said drivin means, one of said furnaces being provide with arearward charging openin and conveyor means for charging sai furnacethrough said opening.

4. The combination with a pair of furnaces and a conveyor, said furnacesand conveyor being arranged substantially in parallel relation andspaced apart equally, of charging apparatus for said furnaces comprisinga track mounted laterally of said furnaces, a carriage movably mountedon said track, horizontal track bars supported by said carriage, saidtrack bars having substantially the same spacing as said furnaces andcon veyor, longitudinally movable charge car rying forks mounted on saidtract: bars, ing means for moving said forks into and out of saidfurnaces, driving means for "'ais ing and lowering said track barsrelati veiy to said carriage whereby said forks are raised and lowered,driving means for moving said carriage on said track substantially atright means for selectively controlling said driving means.

5. The combination with a pair of furnaces and a conveyor, said furnacesand conveyor being arranged substantially in parallel relation andspaced apart equal distances, of charging apparatus for said furnacescomprising a track mounted substantially at right angles to thelongitudinal axes of said furnaces, a carriage movably mounted on saidtrack, horizontal track bars supported by said carriage arranged inparallel and separated a distance equal to the distance between saidfurnaces, longitudinally movable forks mounted on said track bars,driving means for moving said forks into and out of said furnaces,driving means for vertically raising and lowering said track barsrelative to said carriage and driving means for moving said carriage onsaid track and means for selectively controlling said driving means.

6. In apparatus for carrying out successive heat treating operations,the combination of a pair of furnaces and a support constitutingtreating devices, said devices being equally spaced, one of saidfurnaces being provided with a rearward charging opening, conveyor meansfor charging said furnaces through said opening, a carriage movable backand forth in front of said treating devices, and a pair of chargingdevices mounted on said carriage, said charging devices having the samespacing as said treating devices so that said carriage is movable tobring one of said charging devices into successive cooperating relat onwith said furnaces while at the same time the other charging device ismoved into 8 successive cooperating relation with oneof said furnacesand said support,drivin means for said carriage and said chargingevices, and means for controlling said driving means.

In witness whereof, I have hereunto set 10 my hand this 5th dag of June,1928.

J AME L. McFABLAND.

CERTIFICATE or CORRECTION. Patent N 1, s4s,s9s.- Granted March a, 19 32;10

JAMES L. McFARLAND.-

- ltfi s hereby certified that error anpears. in the printedspecification of the.

above; numbered patent requiring correction as follows: Page'4, line 43;strike out the comma after the word "raising" and insert the word andand line 44,

strike out the 'word "and" and insert a comma; and that the. saidLetters Patent shonld'be read with these corrections therein that thesame may conform to the record of the case in the Patent Office.

Signed andsealed this l 7th day of May, A. D. 1932.

M. Moore (sen) ActingComniissioner of Patenta

